Tennis player Sloane Stephens is leaving the biggest name in sportswear behind.
After four years with Nike, the 2017 US Open champion has signed a new apparel endorsement deal with FP Movement, a sister brand to Free People that sells sportswear staples like track shorts and leggings as well as athleisure-friendly pieces such as onesies and fleece jackets. She has worked with Nike since 2018, and previously worked with Under Armour for seven…